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Discussion Starter · #341 ·
I fully approve of this.
Thanks! :D

Holy smoking tyres batman....what gearbox are you using in this thing again ?

Will the SC like hot air from the turbo blowing into it ?

Why not go twin turbos ? or seq. twins ?
Forgot to answer that later part....

The problem will be the supercharger discharge temps. The teflon coating doesn't appreciate temps over 250 deg C and in warm weather and high boost it's cutting very close. Thus a small intecooler between the chargers might be needed.

I got the supercharger for a very reasonable price, which is a major factor, but also it's much easier to design the exhaust the system with a single turbo; also I'm intereted trying out a few ideas. The compound charging setup should have higher scavenging efficiency (much lower exhaust back pressure) and the fact supercharger will literally give boost right from the idle.

That said, the system is so complex and bulky the future wagon project is going to get a VGT system instead.
 

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Discussion Starter · #344 ·
Boost-wise the engine should be a dream to drive, but the daily driver it has a few quite disturbing features - filled block and forged pistons. The side clearance is absolutely huge the pistons are VERY loose when the engine is cold (of course once the engine is warm it's all good and snug) and it is going to sound like a rock crusher while the engine is warming up...
 

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Discussion Starter · #346 · (Edited)
Just to reduce the cylinder wall deformation and the chance of cracking. The system has the capacity to run 3 bar of boost and I'd be a [mangina] not to try it at least once... (actually it should be able to do almost five but I'd be a moron to try that)

It's a half fill actually, there's still plenty of coolant in the cylinder jacket. I wouldn't be too worried about heat issues (after all, the oil jets provide extra cooling for the pistons) and hypotethically it allows a bit faster warming up, which would be really nice in the winter (Ice tracks, hells yeah!)
 

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Discussion Starter · #349 ·
I need to start juggling the schedule between building the car and finishing the engine... anyway, I finally received the turbo, so here's the shots of the both compressor stages:





It's been way way too long, but the engine build is at last on it's final stretch!

The injectors will be Bosch EV14, 2200cc. I dropped the idea for staged injection, too many hassles vs benefits. I'm still thinking about which ignition system to adopt. Plasma ignition sounds interesting, I need to study it a bit to see if it's hogwash or a real deal. Winter starting on E85 is going to need a big spark, for one.
 

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Discussion Starter · #350 ·
Since I thought the AWD would make a great platform for this engine, I concentrated on building it instead of engine. And now as bureaucrats shot that idea down I'm left with two parallel projects. Not a good place to be.

After deciding whether to transplant the engine into some other, more suitable AWD (Mazda 323 GTX, Mitsu Evo, some other) or RWD (Mazda RX-3, RX-7, 616 coupe, MB 190e) I had an MX-6 force-selled on me (not that I complain, it's *mint*) which will be new home for the engine. Sure it's FWD, but I have some ideas how to make it behave. Here's my new beauty:





1989 pre-facelift 2.0 16v GT. Electric mirrors, no AWS and AAS long gone. I havent taken any photos of it myself yet, as it's almost continuously dark (and it's not on my yard actually, it's being stored ATM) and the car is dirty. The car had been kept in a shed for a better part of a decade; it had some electrical problems and stopped running. I did actually do the electrical work on the car a year earlier when it was being re-painted, and it is in top shape. It's practically how these cars were in the mid-nineties. This car will be the host of my new engine.

I decided to solve the transmission problem with the same OEM+ -solution Neville took, and bought an A26M-R transmission from the UK. It was only 320e (~$430US) so I wonder if it's all OK inside, but at that price I can afford to catch up a few missed maintenance routines. Here are the new and old transmission photos, the A26M is a monstrous hunk beside the G5M.





 

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I assume you're going to swap in an MPS-3 gearset also?

I'd be interested to see how you do the mounts for the GD chassis too.
 

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Discussion Starter · #352 ·
I plotted the RPM/speed graph for the diesel box, and it doesn't seem too terrible for use... the MPS3 gearsets I've seen are pretty steeply priced, and if I get decent performance without, I could use the money elsewhere. Anyway it's not on the high priority. I'm counting on supercharger giving good low-RPM performance. Here's the graph:



Apart from the horrible RPM drop from first to second, it doesn't seem too bad. The sixth gear is only usable on motorway (and on Nardo track), but it's that way in the CX-7 too. The 4th gear is about the same fifth was in the original gearbox, but the original seemed a bit too short geared for the turbo anyway.

And no, despite the graph I don't plan on revving it to 7000RPM too often...
 

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Gearbox

STW

It's an awesome gearbox, watch out what mounting you put at the back of the gearbox, if possible try and make a mounting bracket as the original bracket, I payed school fee with mine, 1st threw to 4th gear is quiet good, I only rev to 7500.

BTW my car is boosting 0.9 bar boost and making 280kw on the front wheels
Still running the motor in motor has got 1700km
 

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Discussion Starter · #354 ·
Great to know the stroker doesn't mind revving to 7500 :) (Then again, Cosworth Duratec 23 with similar stroke is revved up to 8000RPM in the 280hp version, so short excursions should be okay for this too. Though I don't expect doing 430 km/h anytime soon :D)

I ran into a new problem with the gearbox; I made the flywheel according to the G-type flywheel (225mm clutch) and the A26 uses Ford flywheel (240mm). I think I'll need to fit the Ford starter ring on the flywheel. The bellhouse has a Crank angle sensor mount, I should see if I could make a trigger wheel too while at it.

The engine mounts will be an interesting part of the project. Given how huge mass increased there already on top of the front axle, there's a good reason to engineer them a bit more carefully. All the extra parts net about 60-70kg of extra to the front; gearbox 70kg, turbo+wastegate+manifold+brace ~25kg, supercharger with bypass valve and mount, ~10kg, intercooler(s) and water within, 3kg... While replacing only max 40kg of stock parts, so you don't want any bit more than you need. If I could source another AWD front subframe I'd use that, since it would place that entire mass about 15mm lower in the chassis. Not to mention the large cross beam between the control arms.
 

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70kg gearbox weight huh....
Makes even the Toyota ones seem like a feather weight in comparison.

To think the original G series is about 40 odd kilos, I suppose there is one advantage at least it evens up the left/right weight distribution at the front.
 

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Discussion Starter · #356 ·
I found some training manual stuff for MS6:


Nothing really new at this point, but this does seem a further proof the FWD and AWD boxes are virtually identical (Unlike G5 FWD/AWD, where absolutely *nothing* swaps.) The transfer unit mounts where there usually is the driveshaft extension support bearing and onto a mount point on the gearbox end.

With my build this opens no new avenues; there is no way I could get an exemption for a coupe, let alone with two decades more modern technology (the amount of electronics involved is pretty overwhelming, for the government official at least, and the control boxes are linked or integrated), plus the known attitude towards high performance builds. However, for those interested in and allowed to do AWD conversions this might be interesting information.
 

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The Toyota E series, the AWD part is more or less bolt on to the FWD version; Toyota started using Aisin gearboxes from about 2003 rather that their own.

Toyota always used alot of Aisin parts in the past, I wonder if this is something learned from Toyota. The two companies may even be partially connected in some way. I've never looked into that.
 

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Discussion Starter · #358 ·
They sure are. Toyota owns 30% of Aisin, making it in practice a Toyota company.
 

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Yes that 5th gear syncro looks very familiar.
 
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